Walter A. Shewhart

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Walter Andrew Shewhart [ ˈʃu: hɑ: ⁠ɹ⁠t ] (born March 18, 1891 in New Canton, Illinois ; † March 11, 1967 in Troy Hills , New Jersey ) was an American physicist, engineer and statistician who occasionally is called the father of SPC (statistical quality / process control) .

Shewhart was born in New Canton, Illinois in 1891 to Anton and Esta Barney Shewhart. On August 4, 1914, he married Edna Elizabeth Hart, daughter of William Nathaniel and Isabelle lipcott Hart, in Pike County, Illinois.

education

Walter Shewhart attended the University of Illinois at Urbana-Champaign , where he completed both his bachelor's and master's degree. In 1917 he was awarded a doctorate in physics by the University of California, Berkeley . He later taught at both the University of Illinois and the University of California. He was also the head of the physics department at the Wisconsin Normal School in LaCrosse.

Work on industrial quality

In 1918, after earning his PhD, Shewhart joined the Western Electric Company to help the engineers who were already working improve the telephone hardware. Western Electric manufactured hardware systems and manufactured telephone equipment for the Bell Telephone Company. Their main operation was in Hawthorne in Cicero, a suburb of Chicago . Shewhart also worked there. However, the company's tasks were limited to checking the finished products and, if necessary, replacing defective products. That changed on May 16, 1924 when Dr. Shewhart wrote a little pamphlet for his company. This comprised a single page. A third of this document was a diagram, the remainder was devoted to the description and explanation of the diagram. The chart included displaying what is now known as a quality control chart. The diagram and the text describe all important principles and considerations of today's process quality control. Shewhart emphasizes in his work the importance of reducing variations in production. He also suggests that continuous process changes in response to problems such as disagreements increase variations. Ultimately, this significantly degrades the quality.

Shewhart divided the problem into expected and coincidental, i.e. non-predictable reasons and designed the quality control charts that should help to differentiate between the two. He also stressed that it is necessary to bring a production process into a state of complete statistical control, in that there are only random, unpredictable reasons that lead to the problem of quality degradation. He also advises that this production process be carefully monitored. This should help to predict the future output and to manage the process economically. With the help of experiments and practical work, Shewhart created the basis for quality control cards and the concept of statistical process control .

Shewhart worked at Western Electric Company until 1925. After that, he finally moved to Bell Telephone Research Laboratories. There he worked in various areas, including factory production. He stayed with the Bell Telephone Company until he retired in 1956.

Later work

From the 1930s on, Shewhart's interests expanded from industrial quality to natural science and statistical inference. He also published two books, Economic Control of Quality of Manufactured Product (1931) and Statistical Method from the Viewpoint of Quality Control (1939). His first work is considered to be a complete and detailed written work of the basic principles of quality process control. In his second work, among other things, he critically examines what natural sciences and statistical practice can learn from experience in the field of industrial quality control. With this work Shewhart also achieved public recognition in the statistical society for the first time. Shewhart has also published numerous articles on process quality control and general statistics in several professional journals. Many of these items can now be found in-house at his former company, Bell Telephone Laboratories. The original version of his historical writing from May 1924 can also be found there.

Shewhart's attitude towards statistics was radically different from that of his peers. He had a strict, operational view that was heavily influenced by the writings of the philosopher Clarence Irving Lewis . This also influenced his work. Shewhart read Lewis' Mind and the World Order in particular.

While Shewhart was teaching in England in 1932 with the assistance of Karl Pearson , his ideas attracted a little enthusiasm within England's statistical tradition. British standards in statistics, while nominally based on Shewhart's work, in fact still deviated from Shewhart's work on serious philosophical and methodological issues.

Shewhart also played an important role in his country during World War II. He served as an advisor to the American Department of War. Using his knowledge of process quality control and statistics in general, he helped raise standards during the war.

Shewhart visited India from 1947-1948 with the sponsorship of PC Mahalanobis from the Indian Statistical Institute . He made several tours around the country, held several conferences and stimulated the interest of Indian industries in statistical quality control and its guidelines.

He died in Troy Hills, New Jersey in 1967.

influence

In 1938 Shewhart's work caught the attention of physicists W. Edwards Deming and Raymond T. Bridge. Both were very impressed with Shewhart's work. In 1934, the two physicists published an article for guidance in "Critique of Modern Physics". After reading Shewhart's findings, they asked the newspaper to rewrite their article in order to adapt it to Shewhart's views.

After this first encounter, Shewhart and Deming began working together for a long time. This included, among other things, the work on productivity during World War II, in which the two were significantly involved, as well as the spread of Shewhart's ideas and approaches by Deming in Japan since the 1950s.

Shewhart cycle

Phases of the PDCA cycle

Deming's further developments of Shewhart's ideas also gave rise to the Shewhart cycle. The physicist W. Edwards Deming developed a scheme in the form of a circle from the methodical ideas and suggestions of Shewhart, which is used for problem solving and originally comes from quality assurance through Shewhart. This is also called the Deming circle or PDCA cycle, after the four different steps to problem solving (plan, do, check / control, act). This method has been further developed to this day and is now a common method for finding solutions to problems in many companies and businesses.

Honors and Achievements

In his death obituary for the American Statistical Association , Deming wrote of Shewhart: “As a man, he was kind, distinguished, never disheveled, and never undignified. He was familiar with disappointment and frustration, including the failure of many writers of mathematical statistics to understand his views. "

Shewhart was both the founder and editor of the Whiley Series of Mathematical Statistics, offices that he held for over 20 years. He was consistently an advocate of free speech and freedom of expression and freedom of the press and was happy to be able to publish something that corresponded to his opinion.

Shewhart was a founding member, partner and intermittent president of the Institute of Mathematical Statistics (IMS). He was also a founding member and first honorary member of the American Society of Quality (AQS). There his influence was very great and is still noticeable today. From this he was the first to receive the Shewhart Medal, which is awarded for technical staff management and is therefore named after him. Shewhart was also a partner and temporarily president of the American Statistical Assosication. He also received the Medal of Honor from the American Society of Mechanical Engineers. His work abroad also earned him several honors and offices. So he was addressed by the Indian Statistical Institute in Calcutta as an honored doctor of science. He was also an honored partner of the British Royal Statistical Society and a partner of the International Statistical Institute.

In general, Shewhart has strongly influenced statistical process control. Early on he helped various companies to improve and accelerate quality control. Shewhart also gained some influence and prestige in the natural sciences and general statistics. Even today his creations and works, such as the quality control cards, the Shewhart cycle, or the two books he wrote, are still used in an adapted form.

See also

Publications

bibliography

  • Deming, W. Edwards (1967) Walter A. Shewhart, 1891-1967, American Statistician, Vol. 21, No. 2. (Apr., 1967), pp. 39-40.
  • Bayart, D. (2001) Walter Andrew Shewhart, Statisticians of the Centuries (ed. CC Heyde and E. Seneta) pp. 398-401. New York: Springer.
  • Fagen, MD ( ed. ) (1975) A History of Engineering and Science in the Bell System: The Early Years (1875-1925)
  • Fagen, MD ( ed. ) (1978) A History of Engineering and Science in the Bell System: National Service in War and Peace (1925-1975) ISBN 0-932764-00-2
  • Wheeler, Donald J. (1999). Understanding Variation: The Key to Managing Chaos - 2nd Edition . SPC Press, Inc. ISBN 0-945320-53-1 .

Web links

Individual evidence

  1. ^ A b c d e M. Best, D. Neuhauser: Walter A Shewhart, 1924, and the Hawthorne factory. In: Quality & safety in health care. Volume 15, number 2, April 2006, pp. 142-143, doi: 10.1136 / qshc.2006.018093 , PMID 16585117 , PMC 2464836 (free full text).
  2. ↑ a b c d e f ASQ: About: Walter A. Shewhart. Retrieved June 3, 2016 .
personal data
SURNAME Shewhart, Walter A.
ALTERNATIVE NAMES Shewhart, Walter Andrew (full name)
BRIEF DESCRIPTION American physicist, engineer, and statistician
DATE OF BIRTH March 18, 1891
PLACE OF BIRTH New Canton , Illinois
DATE OF DEATH March 11, 1967
Place of death Troy Hills , New Jersey